A comet is a heavenly body that resembles a snowball and roams in space while orbiting the Sun. It is formed of frozen gases, rocks, dust particles, and other materials. Upon being frozen, all these materials compact into a ball the size of a small town. A comet also has a long tail, formed of gases and dust particles, that stretches away from the Sun. When a comet’s orbit brings it close to the Sun, the comet heats up and all its components expand. The heated dust and gases form a giant glowing head larger than most planets. Comets that orbit the Sun in a fixed amount of time are called periodic comets (like Halley’s Comet); comets without a fixed schedule are called non-periodic comets (like Hale-Bopp); while still others have no defined orbit (like the Great Comet of 1106). Some comets are lost to science, like the 5D/Brorsen.